The Research On Reconstruction Methods Of Digital Holography3D Image

Living in such a colorful three-dimensional world, people studying in display areaare looking for ways to make objects reappearing with whole information. Followingthe rapid emergence of modern electronic technology, computer technique,optoelectronic components as well as their applications in the optical field and so on,more and more digital technique has been introduced in the field of holographic displaytechnology by which almost the whole object information can be reproduced. Digitalholography has many advantages such as low cost, flexible process of recording andreproducing, fast imaging and convenient for digital storage and real-time processing.Therefore, this technique is widely applied in these areas, for example, in featureidentification, holographic anti-counterfeiting, shape and deformation measurement,medical diagnosis and so on.People have tried and made lots of research in digital holography display. Yet,concerning still exists about how to realize the3D images more rapidly and moreaccurately, to obtain the true color display and to improve the utilization efficiency oflight energy. This paper is mainly aimed at studying the methods of3D digitalholographic representation, and the phase-shifting digital holography is analyzedsystematically. Besides, we propose a way to improve simultaneously the image qualityand the light efficiency. The main contents are as follows:1. Based on the principle of traditional optical holography and the introduction ofclassification of holograms, the digital holography is introduced and its image-formingprinciple and related technologies are studied as well. We research the basic theoryabout digital holography on the whole, so as to lay a theoretical foundation for laterstudy.2. Through introducing the technology of phase unwrapping and simulating on thecomputer, we further master the principle of three-dimension holographic imaging. Inaddition, an accuracy and fast algorithm for phase retrieval, which is based onconventional GS algorithm, is introduced. And based on this algorithm and thegeneralized phase contrast (GPC) method, we have proposed a method of two-dimensional color image projection, which can ensure the quality of imagereproduction and meantime raise the light efficiency.3. Several algorithms of phase-shifting digital holography are introduced. Especially,four-step phase shift algorithm is studied and image reproductions of ideal3D objectsare simulated on the computer. The results show that this method can improve thequality of the reproductive images easily. Furthermore, in order to obtain severalholograms at a time, we describe a parallel phase-shifting digital holography techniquethat can be used in real-time measurement.4. Using un-weighted least square method based on discrete cosine transform (DCT)with position function of residues, we propose a new way to search and remove residues.This method can provide a fast and effective way to find residues and give an accuratephase-unwrapping.